/**
 * libpsd - Photoshop file formats (*.psd) decode library
 * Copyright (C) 2004-2007 Graphest Software.
 *
 * libpsd is the legal property of its developers, whose names are too numerous
 * to list here.  Please refer to the COPYRIGHT file distributed with this
 * source distribution.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * $Id: gradient_overlay.c, created by Patrick in 2006.06.18, libpsd@graphest.com Exp $
 */

#include <math.h>
#include "libpsd.h"
#include "psd_config.h"
#include "psd_system.h"
#include "psd_stream.h"
#include "psd_descriptor.h"
#include "psd_color.h"
#include "psd_rect.h"
#include "psd_bitmap.h"
#include "psd_gradient.h"
#include "psd_math.h"


psd_static void psd_set_layer_gradient_overlay_default(psd_layer_effects_gradient_overlay * gradient_overlay)
{
    gradient_overlay->blend_mode = psd_blend_mode_normal;
    gradient_overlay->opacity = 255;
    gradient_overlay->reverse = psd_false;
    gradient_overlay->style = 0;
    gradient_overlay->align_width_layer = psd_true;
    gradient_overlay->angle = 90;
    gradient_overlay->scale = 100;
}

psd_status psd_get_layer_gradient_overlay2(psd_context * context, psd_layer_effects_gradient_overlay * gradient_overlay)
{
    psd_int length, number_items;
    psd_uint rootkey, type, key;
    psd_uchar keychar[256];
    
    psd_set_layer_gradient_overlay_default(gradient_overlay);

    // Unicode string: name from classID
    length = psd_stream_get_int(context) * 2;
    psd_stream_get_null(context, length);

    // classID: 4 bytes (length), followed either by string or (if length is zero) 4-
    // byte classID
    length = psd_stream_get_int(context);
    if(length == 0)
        psd_stream_get_int(context);
    else
        psd_stream_get_null(context, length);

    // Number of items in descriptor
    number_items = psd_stream_get_int(context);

    while(number_items --)
    {
        length = psd_stream_get_int(context);
        psd_assert(length == 0);
        if(length == 0)
            rootkey = psd_stream_get_int(context);
        else
        {
            rootkey = 0;
            psd_stream_get(context, keychar, length);
            keychar[length] = 0;
        }
        // Type: OSType key
        type = psd_stream_get_int(context);

        switch(rootkey)
        {
            // effect enable
            case 'enab':
                psd_assert(type == 'bool');
                gradient_overlay->effect_enable = psd_stream_get_bool(context);
                break;

            // blend mode
            case 'Md  ':
                psd_assert(type == 'enum');
                
                // TypeID: 4 bytes (length), followed either by string or (if length is zero) 4-
                // byte typeID
                length = psd_stream_get_int(context);
                psd_assert(length == 0);
                key = psd_stream_get_int(context);
                // blend mode
                psd_assert(key == 'BlnM');
                gradient_overlay->blend_mode = psd_stream_get_object_blend_mode(context);
                break;

            // opacity
            case 'Opct':
                psd_assert(type == 'UntF');
                // percent
                key = psd_stream_get_int(context);
                psd_assert(key == '#Prc');
                // Actual value (double)
                gradient_overlay->opacity = (psd_int)(psd_stream_get_double(context) * 2.55 + 0.5);
                break;
                
            // gradient color
            case 'Grad':
                // Descriptor
                psd_assert(type == 'Objc');
                psd_stream_get_object_gradient_color(&gradient_overlay->gradient_color, context);
                break;

            case 'Angl':    // angle
                // Unit psd_float
                psd_assert(type == 'UntF');
                
                // '#Ang' = angle: base degrees
                key = psd_stream_get_int(context);
                psd_assert(key == '#Ang');

                // Actual value (double)
                gradient_overlay->angle = (psd_int)psd_stream_get_double(context);
                break;

            case 'Type':    // gradient style
                // Enumerated
                psd_assert(type == 'enum');

                // TypeID: 4 bytes (length), followed either by string or (if length is zero) 4-
                // byte typeID
                length = psd_stream_get_int(context);
                psd_assert(length == 0);
                key = psd_stream_get_int(context);
                // Gradient Type
                psd_assert(key == 'GrdT');
                gradient_overlay->style = psd_stream_get_object_gradient_style(context);
                break;

            case 'Rvrs':    // reverse
                // boolean
                psd_assert(type == 'bool');
                gradient_overlay->reverse = psd_stream_get_bool(context);
                break;

            case 'Algn':    // align with layer
                // boolean
                psd_assert(type == 'bool');
                gradient_overlay->align_width_layer = psd_stream_get_bool(context);
                break;

            case 'Scl ':    // scale
                // Unit psd_float
                psd_assert(type == 'UntF');

                // '#Prc' = percent:
                key = psd_stream_get_int(context);
                psd_assert(key == '#Prc');
                                
                // Actual value (double)
                gradient_overlay->scale = (psd_int)psd_stream_get_double(context);
                break;

            // offset, not documented
            case 'Ofst':
                psd_assert(type == 'Objc');
                psd_stream_get_object_point(&gradient_overlay->horz_offset, 
                    &gradient_overlay->vert_offset, context);
                break;

            default:
                psd_assert(0);
                psd_stream_get_object_null(type, context);
                break;
        }
    }

    return psd_status_done;
}

#ifdef PSD_SUPPORT_EFFECTS_BLEND
psd_status psd_layer_effects_blend_gradient_overlay(psd_context * context, psd_layer_record * layer, psd_layer_effects * data)
{
    psd_layer_effects_gradient_overlay * gradient_overlay = &data->gradient_overlay;
    psd_bitmap src_bmp, dst_bmp;
    psd_layer_mask_info layer_mask_info;
    psd_int width, height, center_x, center_y, radius_x, radius_y, radius_corner;
    psd_int corner_angle, angle;
    psd_int sign_x = 1, sign_y = 1;

    data->left[psd_layer_effects_type_gradient_overlay] = 0;
    data->top[psd_layer_effects_type_gradient_overlay] = 0;
    data->right[psd_layer_effects_type_gradient_overlay] = layer->width;
    data->bottom[psd_layer_effects_type_gradient_overlay] = layer->height;
    data->blend_mode[psd_layer_effects_type_gradient_overlay] = gradient_overlay->blend_mode;
    data->opacity[psd_layer_effects_type_gradient_overlay] = gradient_overlay->opacity;
    data->width[psd_layer_effects_type_gradient_overlay] = layer->width;
    data->height[psd_layer_effects_type_gradient_overlay] = layer->height;

    if(data->image_data[psd_layer_effects_type_gradient_overlay] == NULL)
    {
        data->image_data[psd_layer_effects_type_gradient_overlay] = (psd_argb_color *)psd_malloc(layer->width * layer->height * 4);
        if(data->image_data[psd_layer_effects_type_gradient_overlay] == NULL)
            return psd_status_malloc_failed;
    }

    src_bmp.width = layer->width;
    src_bmp.height = layer->height;
    src_bmp.image_data = layer->image_data;
    dst_bmp.width = layer->width;
    dst_bmp.height = layer->height;
    dst_bmp.image_data = data->image_data[psd_layer_effects_type_gradient_overlay];

    if(gradient_overlay->align_width_layer == psd_false)
    {
        center_x = context->width / 2 + gradient_overlay->horz_offset * context->width / 100;
        center_y = context->height / 2 + gradient_overlay->vert_offset * context->height / 100;
        center_x -= layer->left;
        center_y -= layer->top;
        corner_angle = (psd_int)(atan((psd_float)context->height / context->width) * 180 / PSD_PI + 0.5);
        angle = gradient_overlay->angle;
        width = (context->width * gradient_overlay->scale + 100) / 200;
        height = (context->height * gradient_overlay->scale + 100) / 200;
    }
    else
    {
        center_x = layer->width / 2 + gradient_overlay->horz_offset * layer->width / 100;
        center_y = layer->height / 2 + gradient_overlay->vert_offset * layer->height / 100;
        corner_angle = (psd_int)(atan((psd_float)layer->height / layer->width) * 180 / PSD_PI + 0.5);
        angle = gradient_overlay->angle;
        width = (layer->width * gradient_overlay->scale + 100) / 200;
        height = (layer->height * gradient_overlay->scale + 100) / 200;
    }
    if(angle < 0)
        angle += 360;
    if(angle >= 90 && angle < 180)
    {
        angle = 180 - angle;
        sign_x = -1;
    }
    else if(angle >= 180 && angle < 270)
    {
        angle = angle - 180;
        sign_x = -1;
        sign_y = -1;
    }
    else if(angle >= 270 && angle <= 360)
    {
        angle = 360 - angle;
        sign_y = -1;
    }
    if(angle <= corner_angle)
    {
        radius_x = width;
        radius_y = (psd_int)(radius_x * PSD_TAN(angle) + 0.5);
    }
    else
    {
        radius_y = height;
        radius_x = (psd_int)(radius_y / PSD_TAN(angle) + 0.5);
    }
    radius_corner = (psd_int)(psd_carm_sqrt((psd_float)(radius_x * radius_x + radius_y * radius_y)) + 0.5);

    switch(gradient_overlay->style)
    {
        case psd_gradient_style_linear:
            psd_gradient_fill_linear(&dst_bmp, &gradient_overlay->gradient_color, gradient_overlay->reverse, 
                center_x - sign_x * radius_x, center_y + sign_y * radius_y, 
                center_x + sign_x * radius_x, center_y - sign_y * radius_y);
            break;
        case psd_gradient_style_radial:
            psd_gradient_fill_radial(&dst_bmp, &gradient_overlay->gradient_color, gradient_overlay->reverse, 
                center_x, center_y, radius_corner);
            break;
        case psd_gradient_style_angle:
            psd_gradient_fill_angle(&dst_bmp, &gradient_overlay->gradient_color, gradient_overlay->reverse, 
                center_x, center_y, gradient_overlay->angle);
            break;
        case psd_gradient_style_reflected:
            psd_gradient_fill_reflected(&dst_bmp, &gradient_overlay->gradient_color, gradient_overlay->reverse, 
                center_x - sign_x * radius_x, center_y + sign_y * radius_y, 
                center_x + sign_x * radius_x, center_y - sign_y * radius_y);
            break;
        case psd_gradient_style_diamond:
            psd_gradient_fill_diamond(&dst_bmp, &gradient_overlay->gradient_color, gradient_overlay->reverse, 
                center_x, center_y, radius_corner, gradient_overlay->angle);
            break;
        default:
            psd_assert(0);
            break;
    }
    
    psd_bitmap_mix_alpha_channel(&dst_bmp, &src_bmp);
    memcpy(&layer_mask_info, &layer->layer_mask_info, sizeof(psd_layer_mask_info));
    if(layer_mask_info.disabled == psd_false && (layer_mask_info.default_color != 255 || layer_mask_info.mask_data != NULL))
    {
        layer_mask_info.left -= layer->left;
        layer_mask_info.top -= layer->top;
        layer_mask_info.right -= layer->left;
        layer_mask_info.bottom -= layer->top;
        psd_bitmap_blend_mask(&dst_bmp, &layer_mask_info);
    }

    data->valid[psd_layer_effects_type_gradient_overlay] = psd_false;
    
    return psd_status_done;
}
#endif

